Naoyuki Maeda1. 1. Department of Ophthalmology, Jichi Medical School, Tochigi, Japan. nmaeda@ophthal.med.osaka-u.ac.jp
Abstract
PURPOSE: To review the evaluation of the optical quality of the cornea by corneal topography. METHODS AND RESULTS: Color-coded maps show qualitatively the characteristics and severity of irregular astigmatism at the entrance pupil. Topographic indices such as the surface regularity index and predicted corneal acuity are derived from computation of the corneal power distribution, and they are highly correlated with high-contrast visual acuity. Fourier analysis can be used to represent the irregular and regular astigmatism components simultaneously. Zernike polynomials can be used to calculate higher-order wavefront aberrations due to the corneal surface. CONCLUSION: Evaluation of the optical properties of the cornea using a corneal topographer is useful for assessing quality of vision.
PURPOSE: To review the evaluation of the optical quality of the cornea by corneal topography. METHODS AND RESULTS: Color-coded maps show qualitatively the characteristics and severity of irregular astigmatism at the entrance pupil. Topographic indices such as the surface regularity index and predicted corneal acuity are derived from computation of the corneal power distribution, and they are highly correlated with high-contrast visual acuity. Fourier analysis can be used to represent the irregular and regular astigmatism components simultaneously. Zernike polynomials can be used to calculate higher-order wavefront aberrations due to the corneal surface. CONCLUSION: Evaluation of the optical properties of the cornea using a corneal topographer is useful for assessing quality of vision.